How to do with offset in DC measurement circuit?

Ras Sharif50

Other Parts Discussed in Thread: TMS320F28335, OPA344

Dear All,

I am sampling a DC bipolar voltage ( -1.5 to 1.5 volt ) and passes through a OPA344 circuit to level up to 1.5 volt using a reference voltage ic. ( ADC of TMS320F28335. )

Please help me how can i treat with offset in the DC measurement circuit?

Regards, Ras

over 5 years ago

0 Joseph Casuga over 5 years ago

TI__Mastermind 35655 points

Hi Ras,

How much offset are you seeing after you passed the signal to the op amp? Can you share your buffer circuit?

Regards,

Joseph

0 Ras Sharif50 over 5 years ago in reply to Joseph Casuga

Genius 3455 points

Hi Joseph,

thank you for the reply.

conditioning circuit:

should i to measure the offset when the input voltage is -1.5?

Regards, Ras

0 Joseph Casuga over 5 years ago in reply to Ras Sharif50

TI__Mastermind 35655 points

Hi Ras,

Thanks for providing the circuit...and good to see you are using TI TINA for your schematics and analysis. I'm assuming that V2 is the reference coming from the F28335 to introduce your offset for the bipolar signal, right? Yes, please indicate the offset when signal is at -1.5V.

Best regards,

Joseph

0 Ras Sharif50 over 5 years ago in reply to Joseph Casuga

Genius 3455 points

Hi Joseph,

thank you for the reply. excuse me for the delay.

please consider there is no any offset now when i develop the circuit.

but i foresee some age-degradation and any other deviation in the future when the circuit is working?

Regards, Ras

0 Joseph Casuga over 5 years ago in reply to Ras Sharif50

TI__Mastermind 35655 points

Hi Ras,

Deviation through circuit ageing is factored in to the datasheet parameters. Let me know if this answers your question.

Best regards,

Joseph

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How to do with offset in DC measurement circuit?